This invention relates to photonic band gap materials and more particularly to 2-pattern photonic crystals that have a large, complete photonic band gap (PBG) [1, 2]. Numbers in brackets refer to the list of references included herewith. The contents of these references are incorporated herein by reference.
Two-dimensional (2D) photonic crystal devices have wide applications in slow light devices [3-5], optical chip components [6, 7], spontaneous emission control devices [8, 9], quantum information devices [10], waveguides [11-14], lasers [15-17], light emitting diodes [18-22] and optical communications [23-25]. For the above applications, the optical wave is classified to two modes according to its polarization: transverse electronic (TE) and transverse magnetic (TM). To date, one of the challenges for photonics is that there is no general method to integrate multiple optical wave control devices for different polarizations onto the same plane at the scale of the wavelength. To solve this problem, we invented a novel set of PBG structures with large, complete PBG and an approach to design on chip devices. The PBG structures, called 2-pattern photonic crystals, do not belong to any know photonic crystal category and have the largest complete PBG reported so far. They come from the superposition of two sub-photonic crystals: one contributes the TM PGB and the other contributes the TE PBG. We demonstrate the unique advantages of the 2-pattern crystals to efficiently and freely mold both TM and TE waves for polarization specific waveguides, crossed waveguide, a wavelength scale polarizer, and a high quality resonator for both polarizations. The 2-pattern photonic crystal and the associated device design are general liable and intuitive. They have the potential to be standard tools for future optical chip devices.